1. Field of the Invention
The present invention relates to a process of voice recognition and to a system of voice command in a "harsh" environment, that is to say one that is strongly disturbed not only by noise, but by various physical and physiological factors which may act on the user.
2. Discussion of the Background
In a harsh environment such as for example that prevailing in the cockpit of a military aircraft, the apparatuses for voice capture, restitution and processing are not optimized, and are even, mostly, poorly implemented. The radio communications between the crew and other speakers are of poor quality. The users communicate with several other speakers (other aircraft, ground stations, the other members of the crew, their own voice back again). These communications are monophonic, affected by interference, fairly unintelligible and are not hierarchized. Furthermore, various physical and physiological factors may disturb the capabilities of the user. Among these factors may be noted in particular the load factor of the aircraft, the oxygen mask, high respiratory pressure, pilot stress. These poor communications, when added to the environmental noise, contribute significantly to the fatigue of crews, and may even harm their health. The helmets which they wear protect them hardly at all from such noise. The only means available to them to try to make these communications somewhat more intelligible are controls for adjusting sound level, this being far from satisfactory. The various apparatuses which implement these sound communications are dissimilar and their characteristics are not always completely compatible. Furthermore, the growing complexity of on-board systems entails an overload of work for the operator, provoking stress, loss of concentration and eventually of efficiency, this being particularly injurious to the pursuance of a mission under the best conditions. In this context, a voice command device with high recognition rate is particularly beneficial since it makes it possible to control a complex system in a relatively direct and natural way without mobilizing the entire attention of the operator, something which is far from being the case when using tactile surfaces, keyboards, multi-position buttons.